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US 2015/0314642 A1Published application
Freewheel hub
AssigneeChristianson Systems, Inc.
InventorsJim Gerhardt, Shannon Hansen
Life of this patent
Estimating the term…
Abstract
The present disclosure provides a bicycle hub that provides improved drive line efficiency and bike-to-rider torque feedback. The drive line efficiencies are due to lower rolling resistance resulting from a novel bearing and sprag clutch configuration, a lightweight design, and immediate torque transfer from the cassette drive to the hub body. The bike-to-rider feedback has been improved as the torque transfer is smooth, predictable, and immediate.
Claims22
A bicycle hub comprising:
- a one-piece hub body defining longitudinal rotational axis, the hub body including an internal cavity that extends from a first end of the hub body to an opposed second end of the hub body, the hub body including an external surface defining a first radially extending spoke support flange located at the first end of the hub body and a second radially extending spoke support flange located at the second end of the hub body and a body portion extended therebetween, wherein the internal cavity of the hub body defines a first internal cylindrical surface defined by a first constant diameter located at the first end of the hub body, a second internal surface adjacent the first internal surface, a third internal cylindrical surface defined by a second constant diameter located adjacent the second internal surface;
- an axle including a first end portion and a second end portion, the axle extending through the internal cavity of the hub body in a coaxial arrangement;
- a first bearing set located at the first end portion of the axle configured to interface between the axle and the first internal cylindrical surface of the hub body to facilitate relative rotation between the axle and the hub body;
- a cassette driver including a longitudinal rotational axis arranged coaxially with the longitudinal rotational axis of the hub body, the cassette driver including an internal cavity that extends from a drive end to an opposed driven end, wherein the drive end includes:
- an annular opening positioned within the hub body and terminating at a distal end, the distal end located between the first and second radially extending spoke support flanges, the second end portion of the axle extending through the annular opening;
- a first external cylindrical surface located at a first radial distance from the longitudinal rotational axis of the cassette driver, the first external cylindrical surface radially overlapping the third internal cylindrical surface of the hub body;
- a second external cylindrical surface located at a second radial distance from the longitudinal rotational axis of the cassette driver, the second radial distance being larger than the first radial distance, the second external cylindrical surface being closer to the driven end of the cassette driver than the first external cylindrical surface, wherein the second external cylindrical surface is harder than the surface of the internal cavity of the hub body and has a surface finish of less than or equal to Rz of 2.5 micrometers;
- and
- a third external cylindrical surface located at a third radial distance from the longitudinal rotational axis of the cassette driver, the third radial distance being larger than the second radial distance, the third external cylindrical surface being closer to the driven end than the second external cylindrical surface;
- a second bearing set located at the second end portion of the axle, the second bearing set configured to interface between the axle and the internal cavity of the cassette driver to facilitate relative rotation between the axle and the cassette driver;
- a third bearing set located between the first external cylindrical surface of the driven end of the cassette driver and the third internal surface of the hub body to facilitate relative rotation between the cassette driver and the hub body;
- a fourth bearing set located between the third external cylindrical surface of the driven end of the cassette driver and the hub body configured to facilitate relative rotation between the cassette driver and the hub body;
- a sprag sleeve pressed into the hub body in radial alignment with a portion of the second external cylindrical surface of the driven end of the cassette driver, wherein the sprag sleeve has a cylindrical internal surface that is harder than the surface of the internal cavity of the hub body;
- and
- an annular sprag cage having a plurality of sprags that are tension biased directly against the second external cylindrical surface of the driven end of the cassette driver and radially aligned with the sprag sleeve.
12 more elements
A bicycle hub comprising:
- a hub body including an annular internal cavity that extends from a first end of the hub body to a second end of the hub body;
- a cassette driver including a drive end and a driven end, the drive end being received within the second end of the hub body, the drive end of the hub body including a stepped outer profile, the drive end of the hub body including a first bearing interfacing cylindrical surface located adjacent a distal end of the second end of the cassette driver having a first diameter, a first sprag interfacing cylindrical surface that is coaxially arranged with the annular internal cavity of the hub body located adjacent the first bearing interfacing cylindrical surface and including a second diameter that is larger than the first diameter, a second bearing interfacing cylindrical surface located adjacent the first sprag interfacing cylindrical surface and including a third diameter that is larger than the second diameter;
- a bearing assembly configured to enable relative rotation between the hub body, the cassette driver, and an axle that extends through the hub body and the cassette driver;
- a cylindrical sprag sleeve that is press fitted into the annular internal cavity of the hub body, the sprag sleeve defining a second sprag interfacing cylindrical surface;
- and
- a plurality of sprags located between the cylindrical sprag sleeve and the first sprag interfacing cylindrical surface, the sprags being in contact with and slidable relative to both the first sprag interfacing cylindrical surface and the second sprag interfacing cylindrical surface, the sprags being biased against the first sprag interfacing cylindrical surface such that the sprags rotate with the cassette driver while sliding relative to the cylindrical sprag sleeve while the hub is in a freewheeling state.
3 more elements
A bicycle hub comprising:
- a hub body including a first end and a second end and an external body portion extending therebetween, the hub body including a one-piece unitary construction with an internal through cavity, the first end of the hub body including a first spoke flange in radial coaxial alignment with a first bearing interfacing surface, the second end of the hub body including a second spoke flange in radial coaxial alignment with a second bearing interfacing surface, the hub body including a bearing support portion between the first end and the second end that is coincident with the maximum hub wall thickness of the hub body located between the first and second spoke flanges, the hub body including a sprag sleeve interfacing surface adjacent the bearing support portion;
- a cassette driver including a drive end and a driven end, the drive end being received within the second end of the hub body, the second end of the hub body including a stepped outer profile including a first bearing interfacing cylindrical surface that radially overlaps the bearing support portion of the hub body and located adjacent a distal end of the second end of the cassette driver having a first diameter, a first sprag interfacing cylindrical surface that is coaxially arranged with an annular internal cavity of the hub body located adjacent the first bearing interfacing cylindrical surface and including a second diameter that is larger than the first diameter;
- an axle that extends through the hub body and the second end of the cassette driver, wherein an external surface of the axle is exposed to the hub body;
- a first bearing interfacing between the axle and the first bearing interfacing surface of the hub body;
- a second bearing interfacing between the axle and an internal surface of the cassette driver to facilitate relative rotation between the axle and the cassette driver, the second bearing located in a portion of the cassette driver that is external of the hub body, wherein the portion of the cassette driver received within the hub body is coaxially arranged and spaced away from the axle;
- a third bearing set located between the bearing support portion of the hub body and the first bearing interfacing cylindrical surface of the cassette driver;
- a fourth bearing set located between the second bearing interfacing surface of the hub body and the cassette driver;
- a cylindrical sprag sleeve that is press fitted into the sprag sleeve interfacing surface of the hub body, the sprag sleeve defining a second sprag interfacing cylindrical surface;
- and
- a plurality of sprags located between the cylindrical sprag sleeve and the first sprag interfacing cylindrical surface, the sprags being in contact with and slidable relative to both the first sprag interfacing cylindrical surface of the cassette driver and the second sprag interfacing cylindrical surface of the sprag sleeve, the sprags being biased against the first sprag interfacing cylindrical surface of the cassette driver such that the sprags rotate with the cassette driver while sliding along in constant contact with the second sprag interfacing cylindrical surface of the sprag sleeve while the hub is in a freewheeling state.
7 more elements
Dependencies are inferred from the claim text.